Read - Speed Reading via RSVP
This extension will soon fail to work when clicking on the icon. The backend logic for parsing the page was handled by Mercury Parser's API, which is being shut down.
I have a new, modern replacement for this extension in the works called "Stutter".
It is already available on Firefox and will soon be ported to Chrome as well. This new plugin runs completely offline and performs much faster than Read. The core RSVP logic remains unchanged. Please check it out.